The traditional yogurt manufacturing process involves heating of milk at temperatures of 85-95° C. for 5-10 min, and then cooling the heated milk to warm temperatures (21-45° C.). Safe and harmless lactic acid bacterial cultures are then added to the warm milk. The culture/warm milk mixtures are then filled into cups or transferred to fermentation tanks. The warm milk/culture mixtures are then incubated at warm temperatures for 2-24 hours until a coagulum is obtained, or a pH of 4.6 of the milk is obtained. The yogurt set in cups is then cooled to below 10° C. The yogurt set in fermentation tanks is stirred and cooled to below 10° C., and then filled into cups as drinkable yogurt or stirred yogurt. The whey in yogurt set in fermentation tanks can be strained by passing over filters, or spinning by centrifugal devices resulting in concentrated/strained or Greek yogurt. Flavors or sweeteners can be added before heating the milk or post-fermentation, while fruits are often added post-fermentation. These resultant yogurt products are stored at refrigeration temperatures during distribution, display, and in homes.
At present, the available shelf-stable yogurts and other cultured dairy products are manufactured by sterilizing in a post-fermentation step, which kills the live beneficial bacteria. It would be beneficial to produce cultured dairy products, such as yogurt, kefir, and sour cream, which could be distributed and stored under ambient or non-refrigerated conditions without diminishing the shelf-life and beneficial qualities of the cultured dairy products. Accordingly, it is to these ends that the present invention is directed.